GB2052437A - Improvements in labelling containers - Google Patents

Abstract

A straight-walled cylindrical body 14 for a two or three piece can is labelled, using polymeric shrinkable film 22 including a heat activatable polymeric adhesive, by preheating the body 14 and preferably the label 22 too; wrapping the label around the body and bonding label and body together; following the bonding step, the label and body are subjected to a necking and flanging operation applied to one or both ends of the body, which is then ready for seaming one or a pair of end closures 28 thereto. The film can comprise layers of nylon, an ethylenic acidic polymer-polyethylene and an ethylenic acidic polymer; the latter can be ethylene-methacrylic acid-zinc methacrylate ionomer. <IMAGE>

Description

SPECIFICATION Improvements in labeling containers The present invention relates to improvements in labeling containers.

Prior art located in a search amongst U.S. patents includes the following: 706,635 issued August, 1902 1,295,300 issued February, 1919 2,029,131 issued January, 1936 2,178,618 issued November, 1939 2,412,528 issued December 1946 3,110,554 issued November, 1963 3,235,433 issued February, 1966 3,072,517 issued January, 1963 3,272,671 issued September, 1966 3,524,568 issued August, 1970 3,733,002 issued May, 1973 3,734,273 issued May, 1973 3,802,942 issued April, 1974 3,863,373 issued February, 1975 3,863,374 issued February 1975 3,863,583 issued February, 1975 3,905,854 issued September, 1975 The bodies of metal containers may be formed in a variety of ways, for example by the processes of impact extrusion or drawing and ironing. A body produced by either process is seamless and has only one open end.Another process starts from flat blanks which are formed into cylinders and have their longitudinal edges secured together in any convenient manner, such as by soldering, welding or by means of an organic adhesive, to form strong, leakproof side seams. The former processes are used in the manufacture of two-piece containers wherein the two pieces are the cylindrically-shaped body with its integral end wall and an end closure which serves as the opposite end wall of the container. The process starting from flat blanks is used in the manufacture of three piece containers wherein there are two separate end closures and the cylindrically-shaped body.

An end closure is conventionally double seamed to its body. There is currently a demand for can bodies to be necked-in to some extent so that the double seams do not project radially outwardly of the body walls but rather form extensions thereof.

Necking-in is also desirable to prevent flange cracking, to minimize abuse to the flange area and to minimise the diameter, and hence cost, of the end closures.

There is an increasing demand that such metal containers contain identifying indicia and decorations on their surfaces in the form of labels.

Film labeling systems provide better aesthetics and greater variety of both substrates and decorative effects than can be achieved through conventional metal lithography and moreover present substantial advantages in the quality of printing. Label systems provide a convenient choice of printing methods which include rotogravure and flexographic methods in addition to offset printing. Printing continuous webs of film instead of individual sheets or cans allows the achievement of higher speeds, multiple color application and better registration. A web fed film printing rotogravure line, for instance, can consist of six or seven color decks and a varnish deck with drying facilities between each deck. Thus a seven-color label can be printed and varnished in a single pass through such a line.

Today, one of the most important advantages for a film label system derives from the ability to printthe film label material in a central location so that problems of air pollution from the use of solvents can be minimised. At the can-making location, the printed film labels are received in large rolls, and there are no solvent fumes emitted from the entire decorating operation in the can-making plant. This can be contrasted with the need where conventional lithography is practised for fume incinerators or other means of solvent disposal in connection with metal decorating inks and varnishes used at each individual metal can plant.

The labels themselves can have varnish or plastic film on top of the ink for improved scuff resistance.

Label changing becomes a much simpler operation because all that is involved is changing one roll of preprinted stockforanother, which only takes a few minutes, without substantially interrupting the production flow in the can line. By way of contrast, printing changes in a postprinting line can mean anywhere from 45 minutes to four hours of interruption for achievement of the new colors and new registra- tion.

Several proceudres have been previously proposed for film labeling metal containers. Such procedures are disclosed in U.S. Patent Nos. 3,863,373; 3,863,374; 3,863,583 and 3,905,854 which are assigned to ourselves. The procedures disclosed in these patents cover a variety of non-stretchable film labels and methods for labeling containers with wrinkle-free, water-resistant film.

Labeling two-piece and three-piece can bodies having end areas reduced in diameter relative to the sidewalls poses problems and none of the various procedures known for labeling containers with plastics film, for example as disclosed in the patents referred to hereinabove, are totally satisfactory for use with necked-in cans or cans having otherthan conventional shape with no end areas of reduced diameter.

Attempts to apply essentially non-stretchable labels to necked-in ends have been unsuccessful because such materials as plastics coated paper, paper/foil and plastics films such as Mylar and Cellophane are found to wrinkle and pucker in the necked-in areas. MYLAR and CELLOPHANE are Registered Trade Marks. The use of shrinkable labels, the aim being to shrink them into necked-in areas, is not entirely successful either.

It is an object of this invention to provide a method for predecorating cans with a plastics label whereby labels conform to the configuration of can bodies including necked-in end areas thereof, and wherein wrinkling of the labels in these areas is at a minimum.

The invention provides labeled two-piece and three-piece can bodies which, after labeling, each have at least one end area of reduced diameter form ing a necked-in open end, the bodies employing plastics, composite film labels.

In practising the invention, containers can be labeled at high speeds without degrading the adhesion and aesthetics oftheir labels even when the containers are subjected to subsequent processing including conditions of severe humidity.

According to the present invention, there is provided a method of producing a metal can body of cylindrical form with a water-resistant, wrinkle free label which is adapted for sealing to one or two end closures, comprising encircling the entire circumferential surface of a straight-walled can body with a thermoplastic composite film label including an adhesive coat, bonding the label to substantially the entire surface of the can body, and thereafter subjecting the can body and its label to a necking and flanging operation to adapt at least one end of the can body for seaming to an end closure, the label and adhesive being of sufficient strength to withstand the said operation without cracking or debonding.

The invention also provides a method of producing a metal can body of cylindrical form with a water-resistant, wrinkle-free label, comprising preheating a substantially straight walled, cylindrical can body and/orthe label to a temperature of at least 185"F, disposing one edge of a thermoplastic film label comprising a polymeric base layer having a heat-activatable polymeric adhesive on at least one of its surfaces in contact with the can body along a line parallel to the body longitudinal axis, wrapping the label around the body and disposing its opposite edge in overlapping relation with the said one edge, bonding the label to substantially the entire circumference of the can body and to itself in the overlap, and thereafter subjecting at least one end of the body and the label overlying the body end to a necking-in operation which produces a neck having the label conforming and bonded to the contour of the necked end.

The method is applicable to labeling the bodies for two and three piece cans, and in connection with the latter has the advantage that the label overlaps can mask the often unsightly side seams. The method can be practised using can bodies already having a reduced diameter end portion. Thus, in a two-piece design there is usually a reduced diameter, inwardly inclined bottom end which it may be desirable to cover, at least in part, by the label. Using suitable label stock, the label can be shrunk onto the inwardly inclined portion after bonding the label to the remainder of the can body.

Embodiments of the invention will now be described in more detail by way of example with reference to the accompanying drawings in which: Figure 1 is an elevational side view of a two-piece necked-in container with a product identifying label fully applied thereto, Figure 2 is an enlarged cross-sectional view of the label on a two-piece straight walled can body priorto necking-in and flanging, Figure 3 is an enlarged fragmentary cross sectional view of the label and can body of Figure 2 after necking-in and flanging, Figure 4 is an enlarged cross-sectional view of the label on a three-piece can body priorto necking-in with parts broken away to show the side seam, Figure 5 is an enlarged fragmentary crosssectional view of the label and can body of Figure 4 after necking-in and flanging, Fkgure 6 is an enlarged sectional view taken on line S6 of Figure 1 showing the label extending into the double seam after necking-in, flanging and seaming operations, and Figure 7 is a flow diagram of the process according to the invention Referringto Figures 1 to 5, containers according to this invention are generally indicated by the reference numeral 10 and each comprises a can body having end areas of reduced diameters. For a seamless two-piece can, the body initially is straightwalled with an open end 12, and a bottom end wall 20 is integrally connected to the side wall 14 by an angled transition edge 16.The bottom wall includes a supporting section 18 which extends inwardly a short way from the lower portion of the transition edge 16 and forms therewith the support upon which the container rests when standing upright position, (Figures 2 and 3), the bottom also featuring a central dome concave when viewed from below, the dome being located within the encircling supporting section 18. For a seamed, three-piece can, the body is straight-walled with open ends 24 and a product-identifying label 22 has been applied to the cylindrical wall. The label is applied preferably with overlapped portions 23, overlying and coinciding with the side-seam 26 of the can body.Application of the label is by a method which broadly comprises: (1) encircling the entire circumferential surfaces of a preheated can body having a cylindrical body wall, with a thermoplastic composite film label; (2) bonding the film label to the entire circumference ofthe can body in a substantially 100% bond and (3) subjecting the labeled body to a necking and flanging operation, the label being designed to withstand the necking and flanging operation without detrimental effect on its appearance or adhesion to the body.

Various combinations of materials may be employed in makingthe unique film labels in practising this invention. Preferably, the film is a composite comprising at least one base layer of either a ther moplasticpolymeric material or an aluminium foil coated on at least one of is surfaces by a polymeric heat-activated adhesive. In more specific embodiments, the composite film comprises as the base layer, aluminium foil or a polyolefin or a polyamide or alternating layers of at least two of these and has on at least one surface of the base of a polymeric adhesive layer. The film must be of high strength and high ductility in orderto withstand the stresses of necking-in.

The composite films may be produced by any conventional and well known method. One such method comprises coextruding melts of the respective polymers through a common die, for example, a flat film die; withdrawing the resultant melt extru date from the die, uniaxially orienting the coex truded film and finally, heat setting the oriented film.

The resulting film will exhibit a predetermined degree of shrinkability Use may be made of its shrinkability when labeling can bodies for two-piece cans, should it be desired to have the label intimately coverthetransition edge 16. In an especially preferred procedure, the film is "extrusion" oriented during its manufacture, e.g., the melt extrudate exits a die gap and is drawn to a substantially reduced film thickness by suitable means such as a cooling roll or take-up roll which draws the melt to the desired ratio and delivers the cooled and set composite to a wind-up roll thereby eliminating the need for specific orienting and heat-setting equipment.

Employing the "extrusion"-orienting technique, suitable films have been prepared where the melt extrudate exits a die gap of 0.096 inch (2.4 mm) and is then drawn to a film thickness of about 0.0005 inch (0.012 mm) or less as a result of the linear speed of the wind-up roll being suitably greater than the extrusion exit speed out of the die gap.

The base layerofthe composite film may be any conventional thermoplastic material. Preferably, such components are polyamides or polyolefins or alternating layers of each, including polyamides such as nylon 6 (polycaproamide); nylon 6,6 (polyhexamethylene adipamide); nylon 6, 10; nylon 11 (poly- 11 - undecanoamide); and nylon 12 (poly- 12 - dodecanoamide). The preferred polyamide is nylon 6. Polyolefins such as polyethylene, polypropylene and ethylene-propylene copolymer may likewise be employed. The preferred polyolefin is polyethylene which may be of low, medium or high density with high density polyethylene (density of 0.94 to 0.96) being especially preferred.

Alternatively, the base layer of the composite film can be aluminium foil. Preferred foils are of relatively strong alloys rather than the pure metal.

The polymeric adhesive component of the composite must be one capable of exhibiting high bonding strength to metal, to prevent delamination of the label as the can body is necked and flanged. Generally, such polymers are acidic ethylenic polymers including: ethylene-acrylic acid copolymers ethylene-ethyl acrylate-acrylic acid terpolymers ethylene-methacrylic acid copolymers ethylene-methacrylic acid-metal methacrylate interpolymers (ionomers) ethylene-acrylic acid-metal acrylate interpolymers (ionomers) where metallized ionomers are employed, the metal is a mono, di, or trivalent metal of Groups I, II, III, IV-A and VIII of the Periodic Table of Elements and especially Na, K and Zn.

Such polymers may be prepared by methods well known in the art, particularly as described in U.S.

Patents 3,335,319 and 3,264,272, wherein the polymers are obtained by co-polymerization of a mixture of the olefin and the carboxylic monomer with or without partial neutralization of the acid monomer with a metal ion.

Particularly preferred as the adhesive herein are metal ionic copolymers of ethylene/acrylic acid or ethylene methacrylic acid, ionically crosslinked with Zn++ wherein at least 10 percent of the acid copolymer is neutralized by the metal ion. Such components are available commercially under the Registered Trade MarkSURLYN (E.l. du Pont and Co., Wilmington, Del.) and are especially effective for the purposes ofthis invention.

The thicknesses of the various layers of the composite may vary as desired. The films may be from about 0.85 to 5 mils (0.021 to 0.125 mm) preferably 1 to 3 mils (0.025 to 0.075 mm) in thickness. The base layerwill generally vary from about 0.5 to 1.5 mils (0.012 to 0.037 mm) while the adhesive layer will vary from about 0.1 to 0.5 mils (0.002 to 0.012 mm).

Such materials employed as labels herein are preprinted and, in general, may include an ink layer and a protective varnish layer applied to a non adhesive surface of the label. The materials may be uniaxially oriented prior to application to the can body, if desired, to enable it to shrink e.g. to conform to the transition edge of a two-piece can body. Specific labels include uniaxially oriented 2-layer composites comprising 1.2 mils (0.031 mm) high density polyethylene and 0.3 mils (0.0075 mm) Surlyn (ethylene-methacrylic acid-zinc methacrylate ionomer) as well as 0.0003 mils aluminium foil (0.0075 mm).Another specific example is a coextruded, oriented, four-layercomposite film comprises ing layers, taken in order, of polycaproamide, an acidic ethylenic polymer, polyethylene and acidic ethylenic polymer; the acid ethylenic polymer can be ethylene-methacrylic acid-zinc methacrylate ionomer.

The present labeling process is directed primarily to the problems inherent in labeling necked-in containers. The thickness of the label material is critical to successful operation, for clearances in the tooling which accomplishes the necking-in are very small.

Thus, the label material must be extremely thin and deformable to avoid interference with the necking-in operation while exhibiting an ahesive bond strength strong enough to resist delamination. Thickness is particularly important in the label overlap area where the edges of the label overlap and are sealed one to the other on the container. Labels that are too thick for tooling clearances or that do not exhibit sufficient bond strength will interfere with the necking-in operation causing jams, peeling of the label and/or cracks in the metal shell. It has been found that plastics/adhesive labels varying in thickness from about 2.5 to 3 mils (0.062 to 0.075 mm) may be satisfactorily employed while aluminium foil/adhesive labels varying from 2.5 to 3 mils are also satisfactory.

Additionally, it is essential that the label be 100% bonded to the can body surface and wrinkle-free both before and after subjecting ittothe necking-in operation, 100% bonding meaning there is bonding over the entire label/body interface. The labeled containers may be intended for use with products requiring sterilization of pasteurization and therefore must be sufficiently water-resistant to withstand severe conditions of moisture and/or humidity. Less than 100% bonding of the label or wrinkles permit moisture to get between the label and the body wall causing blistering and rusting as well as an unsatis factory aesthetic appearance. It is therefore essential that the label be wrinkle-free and moisture-resistant.

The labeled containers made according to the invention have been found to maintain excellent adhesive and aesthetic properties after immersion in a water bath at 160 degree F (71 "C) or higher for 5 minutes or when subjected to water spray at 140 degree F (60"C) for 20 minutes, these being conditions simulating those met in sterilization and pasteurization, respec tive ly.

With reference to Figure 7 which is a flow diagram of the method of the invention, two-piece or threepiece straight walled metal can bodies made for example of aluminium, steel and tin-free steel are formed by any suitable method well known in the art and, if desired, after treating the interior thereof with a suitable coating, are fed, by any convenient means such as a conveyor, to a heating station such as an oven. In the heating station the bodies are preheated to a temperature sufficient to aid in activation of the adhesive, preferably from 185 degrees Fto 350 degrees F (85 to 1760C) the exact temperature being dependent on the particular adhesive and film employed. From the oven, the containers are transferred by suitable means, for example by a magnetic turret or conveyor to a labeling station.Labels which have been supplied in suitable form, preferably in preprinted coiled stock, are precut to proper width, gre aterthanthe height of the sidewall 14, and proper length, corresponding to the can circumference plus the required overlap. The label is preheated prior to application to the can body to a temperature sufficient just to activate the polymeric adhesive, normallywithin a range of 185 degrees to 250 degrees F (85 to 121"C), again the exact temperature being determined by the particular adhesive component of the film.In operation of the process, which generally involves labeling at speeds of about 175 to 800, preferably 600 to 800 cans per minute, it is preferred to preheat both the containers and the label to achieve rapid adhesive activation and bonding of the label to the container as well as to itself in the overlap area.

While it is possible to effect bonding by heating either the containerorthe label, such a procedure is considerably slower and does not readily lend itself to high speed labeling procedures. In operating the present process it is necessary for the adhesive on the leading edge of the label to become tacky within one second of contact with the metal can body. Such rapid adhesive activation is accomplished by preheating both the label and the container.

After preheating and activation of the adhesive component of the film label, a leading edge of the label is contacted with the preheated can body and the label is wound around the body making a substantially 100 percent, 360 degree bond. A trailing edge portion substantially overlaps the marginal portion of the leading edge of the label and adheres thereto with bonding being assisted preferably by pressure applied from a resilient pad or roller.

Having applied and bonded the label to the can body, the latter is conveyed to tooling at a necking-in and flanging station, for necking and flanging. These operations are performed by appropriate deforming forces exerted on the can body ends and on the overlying label portions bonded thereto. The tooling has clearances adequate to accommodate the metal can body and the bonded label thereon. After necking and flanging, the bodies are ready for closing by seaming end closures to their open ends; the labeling can be such as to extend into the seam region, as shown in Fig. 6. Bodies for two-piece cans will be necked and flanged attheirtop ends only, while bodies for three piece cans will be necked both ends.

In some instances, it may be desired to cover the transition edge 16, or part thereof, and possibly part of the supporting section 18 by the label. Afterbonding the label to the right cylindrical main part of the body by the tOO% bond, a lower edge region ofthe label is caused to contact and bond the reduceddiameter transition edge 16 and our section 18. This is achieved by shrinking the label by heating to a temperature above the bonding temperature but below the label flow temperature.For the Surlyn Polyethylene film described above, and oriented and annealed at about 275"F (1 350C), the adhesive can be activated without shrinking the label at 240 to 2500F (115 to 121 C), while shrinking can be accomplished by heating for adequately prolonged periods to 290"F (143"C) or greater. At this temperature destructive flow is avoided. Heating can be by means of hot air, flame, heat bars or sealers treated to avoid sticking; heat generated from microwave or infra-red sources can also be employed. Preferably, the label overlap overlying the end portion is held in position during the shrinking operation by suitable means such as a brush, roller or pad to prevent overlap portions from folding back or curling onto the label.

It is also preferred, after shrinking, to contact the portion of the label shrunk onto the reduced diametertransition edge with suitable smoothing means such as a roll, resilient pad or brush.

The method according to the invention is applicable to seamless two-piece cans as well as welded, cemented lap or soldered necked-in cans with equally good results. While it is not absolutely necessary to orient the side seams of these containers with the label edges to obtain a smooth, wrinklefree label, side seam orientation is highly desirable and is preferred. All of the above types of sideseamed cans have some roughness, irregularity or lack of smoothness at the side seam, and it is undesirable for this roughness to show through the thin label in a random pattern. The darkness or poor appearance of the soldered side seam has already been described, and a side-seam oriented label, i.e.

with the overlap coinciding with and overlying the side seam, will conceal this darkness, assuming the overlap area is opaque. In a welded can, there is often a very dark, blue-black weld line along the side seam, so side seam orienting is preferred. The cemented side seam is perhaps the best of the three from an appearance standpoint, but even so it has a step or overlap joint of approximately .008" depth, (0.20 mm), that will appear unsightly through the label unless side seam orientation of the label is employed.

Thus, it is preferred, prior to application of the label, to orient the side seam of the can body so that the leading edge of the label is vertical i.e. parallel to the major axis of the can. Unless this is done, the label may adopt a spiral configuration and there is a likelihood that some bare metal will show th rough near the ends of the can. It should be recognized that it is normal for dimensionai variations to be found in the height of the can and the slit width of the label materials, so that it is possible that some bare metal might show even if a spiraling configuration does not exist. One advantage of the method employed herein over other labeling systems is that the labels can be extended into the double-seam area 28 (Figure6).

Positioning of the leading edges of labels within the bow of a side seam to eliminate wrinkling, in part, forms the subject matter of U.S. Patents 3,863,373 and 3,905,854, entitled, respectively, "Labeled Side-Seamed Can Body", and "Method of Providing a Labeled Side-Seamed Can Body", which are assigned to us, and reference to these patents is directed for further information.

Orientation of the container bodies is preferably accomplished by the method and apparatus described in U.S. Patent 3,988,182, entitled "Side Seam Orientation In Can Labelling Machine" which is assigned to us. As disclosed, the method and apparatus orients the side seam horizontally and introduces a fluid such as air under pressure and at a volume sufficient to buoy the containers whereby gravity orients the side seams prior to delivery to the labeling station.

The method according to this invention provides means for producing film labeled can bodies that possess all of the qualities above enumerated, including freedom from wrinkles and sufficient water-resistant to withstand severe conditions of moisture and/or humidity. Since, depending on the product with which the containers will be filled, the labeled containers may be subjected to sterilization, pasteurization, or other process involving moisture, it is essential that moisture-resistance be inherent in any label suitable for use therewith. The labeled containers disclosed have been found to maintain excellent adhesive and aesthetic properties after immersion in a water bath at 1 60"F for 5 minutes (the standard leakage test for aerosol containers) or when subjected to a water spray at 140"F for 20 minutes, as in a pasteurization process.

Claims (30)

1. A method of producing a metal can body of cylindrical form with a water-resistant, wrinkle free label which is adapted for sealing to one or two end closures, comprising encircling the entire circumferential surface of a straight-walled can body with a thermoplastic composite film label including an adhesive coat, bonding the label to substantially the entire surface of the can body, and thereafter subjecting the can body and its label to a necking and flanging operation to adapt at least one end of the can body for seaming to an end closure, the label and adhesive being of sufficient strength to withstand the said operation without cracking or debonding.

2. A method of producing a metal can body of cylindrical form with a water-resistant, wrinkle-free label, comprising preheating a substantially straight walled, cylindrical can body and/orthe label to a temperature of at least 185"F, disposing one edge of a thermoplastic film label comprising a polymeric base layer having a heat-activatable polymeric adhesive on at least one of its surfaces in contact with the can body along a line parallel to the body longitudinal axis, wrapping the label around the body and disposing its opposite edge in overlapping relation with the said one edge, bonding the label to substantially the entire circumference of the can body and to itself in the overlap, and thereafter subjecting at least one end of the body and the label overlying the body end to a necking-in operation which produces a neck having the label conforming and bonded to the contour of the necked end.

3. A method as claimed in claim 1 or claim 2, in which the can body is preheated before application of the label to a temperature in the range of 185 to 350"F.

4. A method as claimed in claim 1,2 or3, in which the can body provided is seamless and has integral bottom and side walls connected by an angled transition edge, and the label which is thermocontractive is shrunk to conform to at least a portion of the transition edge subsequent to the label bonding step.

5. A method as claimed in claim 4, in which the bottom wall includes a supporting surface connected with the angled transition edge, and the label is shrunk to conform to both the transition edge and to at least a portion of the supporting surface.

6. A method according to claim 4 or claim 5, wherein shrinking is accomplished by heating the label to a temperature greater than that at which the adhesive is activated and lower than that at which destructive flow of the label occurs.

7. A method as claimed in claim 1,2 or3, in which the can body provided is side-seamed and the said one edge of the label is positioned to contact the can body parallel and adjacent to the side seam.

8. A method as claimed in claim 7, in which marginal edge portions of the said edges of the label are disposed so as to overlie one another and the side seam.

9. A method as claimed in claim 7, in which the side seam includes a juncture on the exterior wall of the can body and an inward bow, and the overlapped edges of the label overlie and coincide with the exterior juncture and the bow.

10. A method as claimed in claim 7,8 or 9, in which the overlap of the label overlying the side seam of the body wall is opaque.

11. A method as claimed in any of claims 7 to 10, in which the can body is oriented to position the side seam along an axis in the same plane as the said one edge of the label prior to bonding the label to the can body.

12. A method as claimed in any of claims 1 to 11, in which the label applied is a coextruded, oriented, two-layer composite film comprising polyethylene and an ethylenic acidic polymer.

13. A method as claimed in any of claims 1 to 11, in which the label applied is a coextruded oriented, four-layercompositefilm comprising polycaproamide, an ethylenic acidic polymer, polyethylene and an ethylenic acidic polymer.

14. A method as claimed in claim 12 or claim 13, in which the ethylenic acidic polymer is ethylene methacrylic acid-zinc methacrylate ionomer.

15. A method as claimed in any of claims 1 to 14, in which the label is heated to a temperature of 185 degrees to 250 degrees F before application to the can body.

16. A method of labeling can bodies substantially as herein described with reference to the accompanying drawings.

17. A labeled can body produced by the method claimed in claim 1 or claim 2.

18. A can body as claimed in claim 17, in which the label is a composite film comprising a thermocontractive, thermoplastic polymeric base layer having on at least one of its surfaces a heat-activated polymeric adhesive.

19. A can body as claimed in claim 18, in which the base layer is selected from polyamides, polyolefins and alternating layers of each and the adhesive is an acidic ethylenic polymer.

20. A can body as claimed in claim 19, in which the label is a coextruded, oriented, two-layer composite film comprising polyethylene and an acidic ethylenic copolymer.

21. A can body as claimed in claim 20, in which the acidic ethylenic copolymer is ethylene - methacrylic acid - zinc methacrylate ionomer.

22. A can body as claimed in claim 19, in which the label is a coextruded, oriented, four-layer composite film comprising polycaproamide, an ethylenic acidic polymer, polyethylene and an ethylenic acidic polymer.

23. A can body as claimed in claim 22, in which said ethylenic acidic polymer is ethylene - methacrylic acid - zinc methacrylate ionomer.

24. A can body as claimed in any of claims 18 to 23, in which the label has printed identifying - indicia on a non-adhesive surface thereof.

25. Acan body as claimed in any of claims 18 to 24, which is a body for a two-piece can and has integral bottom and side walls connected by an angled transition edge, the label conforming to at least a portion of the transition edge.

26. A can body as claimed in claim 25, in which a container supporting surface is integrally connected with the angled transition edge, and the label conforms to the contour of the transition edge and to at least a portion of the supporting surface.

27. A can body as claimed in any of claims 18 to 24, which is a side-seamed body for a three-piece can, and opposite marginal edge portions of the label are in overlapping relation one to the other, the overlap overlying the side seam.

28. A can body as claimed in any of claims 18 to 27, in which an end closure constituting at least a top container wall is seamed to the necked and flanged area, and the label has an edge thereof located within the seam.

29. A labeled container substantially as herein described with reference to and as shown in Figs.1 1 to 3, or Figs. 4 and 5, and Fig. 6 of the accompanying drawings.

30. A labeled can body of straight-walled cylindrical form except in a region confined to one end or both opposite ends thereof whereat the body wall terminates in a neck and an out-turned flange, the body including said necked and flanged region(s) having a thermoplastic polymeiric label bonded in a 100% bond thereto by a heat-activated adhesive, the label being bonded to and conforming to the entire body wall portion defining both the neck and flange.